A riding lawn mower accommodates a cutter blade in an elevatable cutter deck, and mows lawn grass with the cutter blade. A plurality of cutter blades is often arranged in the width direction of the vehicle. The lawn-cutting height can be varied by adjusting the height of the cutter deck. The transmission section provided at the top of the cutter deck is covered by a cover. Such a riding lawn mower is known from, for example, Japanese Utility Model Application Laid-Open Publication No. 63-193411 (JP-U 63-193411 A), Japanese Utility Model Publication No. 07-7695 (JP-U 07-7695 B), and Japanese Utility Model Application Laid-Open Publication No. 02-148226 (JP-U 02-148226 A).
The riding lawn mower disclosed in JP-U 63-193411 A has a structure in which a cutter deck is elevatably mounted using a link mechanism in the center section of the vehicle body, a plurality of cutter blades is accommodated in the cutter deck, and a cover is mounted on the link mechanism. The cover covers only the transmission section and is arranged on the upper surface of the cutter deck.
The riding lawn mower disclosed in JP-U 07-7695 B has a structure in which a cutter deck is elevatably mounted using a link mechanism in the center section of the vehicle body, a plurality of cutter blades is accommodated in the cutter deck, and a cover is mounted on the link mechanism. The cover covers the right and left sides of the transmission section excluding the center portion.
The riding lawn mower disclosed in JP-U 02-148226 A has a structure in which a cutter deck is elevatably mounted using a link mechanism in the center section of the vehicle body, a plurality of cutter blades is accommodated in the cutter deck, and a cover is swingably mounted in the vertical direction on the upper surface of the cutter deck. The cover covers the transmission section and serves as a floor on which the vehicle occupant rides when the cover placed over the upper surface of the cutter deck.
A transport airflow (rotation wind) is generated inside the cutter deck when the cutter blades rotate and perform a mowing operation. The transport airflow is used for transporting the cut grass clippings from the cutter deck to a grass clippings container (the bagging method). The transport airflow is used for discharging grass clippings from the left or right side of the cutter deck in relation to the forward direction of the riding lawn mower (side discharge method). However, a portion of the transport airflow escapes from the edge of the cutter deck and moves upward (blows upward). In particular, since the cutter deck for accommodating a plurality of cutter blades is large, the flow of the transport airflow that escapes from the edge and moves upward is also considerable. The transport airflow that has moved upward includes grass clippings. A portion of the dispersed grass clippings may be deposited on the upper surface of the cutter deck. Since a cover that covers the transmission section is arranged on the upper surface of the cutter deck, a portion of the dispersed grass clippings may enter the gap between the cutter deck and the cover. Grass clippings that have entered inside the cover are difficult to discharge.